Swab



July 21, 1942. A. PARMESON SWAB Filed Feb. 23, 1938 2 Sheets-Sheet 2llldlldll v 11% Patented July 21, 1942 UNITED STATES PATENT OFFICE SWABAugustine Parmesan, Houston, Tex.

Application February 23, 1938, Serial No. 192,003

4 Claims.

This invention relates to a swab.

An object of the invention is to provide a swab of the characterdescribed specially designed for use in removing fluid, particularly theheavy drilling fluid, from a well, preparatory to bringing in the well.

It is another object of the invention to provide a swab of the characterdescribed that will readily move to open position as it moves downwardlythrough the fluid but which, upon upward movement of the swab will closeto trap the fluid in the well pipe above it so that the trapped fluidmay be discharged from the well as the swab is pulled upwardly.

It is a further object of the invention to provide, in a swab, a noveltype of sectional swab rubber or packing of such construction that uponmovement of the swab downwardly through the fluid the sections willseparate to permit the passage of the well fluid but upon upwardmovement of the swab the complementary sections of the swab rubber willmove into closed position to completely close the space between the wellpipe and the swab mandrel whereby the liquid above will be dischargedfrom the well upon upward move- 75 ment of the swab.

It is a further object of the invention to provide in a swab, asectional swab rubber, whose sections are so shaped that theircontacting faces 'will fit closely together when the swab is in activeposition to prevent the leakage of the well fluid past the swab rubber.

A further object of the invention is to provide a swab of the characterdescribed of such construction that a vacuum will not be formed beneaththe swab as the swab moves upwardly, there being an air channel throughwhich air may be permitted to enter the wellbeneaththe swab. It isusually not desirable to permit the creation of a vacuum or partialvacuum beneath the swab during. the swabbing operations for the reasonthat if a vacuum is so created sand from the surrounding stratum may bedrawn into the well or if the pressure on a producing stratum issudden.. 1y relieved by creation of such vacuum, a blowout may. bethereby induced and for that reason provision-has been made forrelieving the vacuum beneath the swab.

It is another object of the invention to provide a swab having an airconduit therethrough for relieving the vacuum beneath but which may beclosed if it should be desired to produce a vacuum beneath the swab. 7

With the above and other objects in view, the invention has particularrelation to certain novel features of construction, operation andarrangement of parts an example of which is given in this specificationand illustration in the accompanying drawings, wherein:

Figure 1 shows a side view of a swab shown partly in section, showingthe swab rubbers in closed position.

Figure 2 shows a fragmentary side view showing the swab open or in theposition it will occupy in passing downwardly through the well fluid.

Figure 3 shows a fragmentary side view taken at right angles to the viewshown in Figure 2.

Figure 4 shows a cross sectional view taken on the line 4--4 of Figure1.

Figure 5 shows an enlarged fragmentary vertical sectional view, showingthe swivel and cable socket.

Figure 6 shows an enlarged fragmentary vertical sectional view showingthe upper end of the carrier.

Figure '7 shows an enlarged fragmentary vertical sectional view showinga type of swab rubber employed.

Figure 8 shows a fragmentary perspective view of another embodiment ofthe swab rubber, and

Figure 9 shows a side elevation of a complete swab shown in active orclosed position, in a well pipe.

Referring now more particularly to the drawings, wherein like numeralsof reference designate the same parts in eachof the figures, the numeralI designates a tubular mandrel whose lower end may be outwardly threadedas at 2 to receive a cap 3 as shown in Figure 1 to be used in case itmay be desired to close the lower end of the mandrel. A reducing nipple4 is screwed on to the upper end of the mandrel and the lower end of atube 5 may be attached to said reducing nipple 4. This tube 5 may be ofany desired length and may be in the form of a metal pipe or a flexiblehose whichever may be selected. A swivel 6 is connected to the upper endof the tube 5 and a nipple l is connected to the upper end of theswivel. The swab may be manipulated by means of a suitable cable 8 whoselower end is attached to the upper end of the nipple l by means of theconventional socket 9. is operated from the ground surface and ispermitted, by the swivel, to turn as may be required during the swabbingoperation. The nipple 1 has a cross bore l0 and leading from this crossbore there is a lengthwise bore II which is connected into thepassageway through the tube 5 an mandrel l.

Secured on the mandrel l and spaced the re- The cable quired distancebeneath the nipple 4 there is a half-round, fixed anchor I2 which isnested with the mandrel and secured thereto in any suitable manner, asby set screws I3. On this anchor are fastened th upper and lowersections I4, I5 of the swab rubbers, hereinafter to be more accuratelydescribed.

Slidably mounted on the mandrel I there is the movable anchor or carrierI6. This carrier is half-round and is nested with the mandrel oppositethe fixed anchor I2 and its upper and lower ends terminate in the upperand lower sleeves II, I8 which are fitted around and slidable on themandrel. These sleeves preferably have rubber lining I9 so that sandwill not so readily collect between the sleeves and mandrel and congesttherein to prevent the movement of the carrier on the mandrel. Themovable anchor or carrier I6 is of somewhat greater length than thefixed anchor I2 so that the distance between the sleeves ll, I8 will besomewhat greater than the length of the fixed anchor I2. On the carrierI 6 are the upper and'lower sections I-I'a, I5a, which are complementaryto the corresponding sections of the sections I4, I5, so that when saidcorresponding sections are in coinciding relation as shown in Figures 1and 9, they will close the space between the mandrel and the well pipe20 in which the swab works.

The. complementary sections I4, I411 and I5, I5a, may be secured ontheir respective anchors in any suitable manner as, for example, by setscrews 2I, asshown in Figure 2. The sections I4, I5 as shown, are ofdifferent construction, but it is to be understood that the swab rubberscomposed of the sections I4, M11 or the swab rubbers composed of thesections I5, I5a may be used interchangeably.

Each section I4, or Ma is composed of a supporting cage 22 having anexternal circumferential groove 23 to receive the packing material as24. Each section I5, I5a is composed of a half round lower end ferrule25 into which. the lower end of the half round packing material 26, suchas rubber, is fitted, as more clearly shown in Figure '7. The rubber 26is secured in the ferrule by being molded about a. corrugated, halfround, cup shaped anchor 21, preferably formed of metal and which issecured in place by means of the bolts 29 which are fitted upwardlythrough the bottom of the ferrule and whose upper ends are threaded tothe lower end of the anchor 21 as shown in Figure '7.

A series of upstanding flexible rods 29 have their lower ends inwardlyturned through the material 26 adjacent the upper end of the ferrule andthey closely embrace said material 25 and their upper ends are attachedto an open, expansible metal ring 30 whereby the rubber 26 is protectedand maintained in place.

It is to be noted that the contacting faces of the sections I4, Ma andI5, I5a are diagonal with respect to the axis of the mandrel I and inthe form shown in Figure 8, the said faces of the section I4b divergefrom each other and the opposing faces of the section I4c fit againstthe faces of the section I4b with wedge like effect so as to form a veryclose fit to prevent leakage. In use, the swab may be assembled as shownin Figure 9 and attached to the lower end of the cable 8 and loweredinto the well. When the swab becomes submerged in the liquid in the wellthe buoyancy of the sections I411. and I4!) will cause said sections tobe retarded by the liquid and themandrel I will move downwardly relativeto the carrier I6 until the lower end of the anchor I2 contacts with theupper end of the sleeve I8. In this position the sections I4, I5 of theswab rubbers will be staggered with relation to the sections Ma and l5aas shown in Figures 2 and 3 so that the swab will readily movedownwardly through the liquid, there being a free passageway for liquidbetween the sections of the swab rubbers. As stated the contacting facesof the sections of the swab rubbers are diagonal. The angle is such,however, as to permit the sections I4, I5 to move downwardly relative tothe section I4a, I5a as above stated. The liquid to be removed will thuspass above the swab. Upon upward movement of the swab, the mandrel Iwill move upwardly relative to the carrier It so as to carry thesections I4, I5 into coinciding, relation with the correspondingsections I 4a, I'5a, so as to completely trap the liquid above andprevent it from escaping past the swab as the swab moves upwardly, thecontacting faces of the sections of the swab rubbers forming fluid tightjoints. As the swab is pulled upwardly the liquid above it will becarried upwardly and eventually discharged from the well. A vacuum willnot be formed beneath the swab, however, for the reason that air will bepermitted to enter through the bores II), II and pass downwardly throughthe tube 5 and the mandrel I and be discharged into the well from thelower end of said mandrel as indicated by the arrows in Figures 5 and 9.

If, however, it should be desired to create a vacuum in the well beneaththe swab, during the swabbing operation, the lower end of themandrel maybe closed by the cap 3 which may be screwed thereon as indicated inFigure 1-.

The tube 5 may be extended any desired distance above the swab rubbers.If the swab is lowered into the liquid at a depth which would otherwiseoverload the swab upon upward movement thereof, the excess liquid abovethe swab may drain out through the bores Ill, II and through the tube 5and the mandrel I so that the load of liquid sustained by the swab, uponupward movement, will be only the liquid trapped between the upper swaband the bore II);

It sometimes happens in swabbing that strong gas pressure beneath theswab will be developed. In such event the excess pressure will berelieved by passing upwardly through the mandrel I and tube 5 and outthrough the bores II], II and then on upwardly from the well.

The drawings and description disclose what is now considered to bepreferred forms of the invention by way of illustration only while thebroad principle of the invention will be defined by the appended claims.

What I claim is:

l. A swab shaped to be lowered into a well containing liquid, andcomprising a tubular mandrel, a nipple mounted on the upper end of saidmandrel, tubular connecting means connected into said nipple at one end,a swivel means connected to the other end of the nipple, a cable socket,a tubular nipple mounted between said swivel and cable socket, said lastmentioned nipple having a cross bore therein connected to the passagewaythrough the mandrel, sectional sealing means mounted on said mandrelrelatively movable into spaced relation upon downward movement of saidmandrel and into coinciding relation upon upward movement of themandrel.

2. A swab for wells comprising a mandrel, sealing means on the mandrelformed of sections, one of said sections being fixed relative to themandrel, upper and lower stops fixed on the mandrel one above and theother beneath the fixed section, a longitudinally movable sectioncarrier on the mandrel having upper and lower sleeves slidable on themandrel and forming stops engageable with the stops fixed on the mandrelto limit the range of movement of the carrier, the other section beingfixed on said carrier, whereby said sections are relatively movable intospaced relation upon downward movement of the swab to provide apassageway for liquid between said sections and the sections beingrelatively movable into coinciding relation upon upward movement of theswab to form a complete seal between the mandrel and the walls of thewell, said fixed and movable stops form'- ing means for limiting therelative movement of said sections in each direction.

3. A swab for wells comprising a mandrel, a fixed and a movablesemi-cyclindrical shell around the mandrel, the movable shell beinglonger than the fixed shell, sleeves slidably connecting the ends of themovable shell to the mandrel and being arranged to co-act with the endsof the fixed shell to limit longitudinal movement of the movable shell,sealing means formed of sections, one of which is on the movable shelland the other being on the fixed shell, said sections being positionedon the shells so that they are in confronting relationship when themovable shell is in one extreme longitudinal position and are spacedapart when the movable shell is in the opposite extreme position.

4. A swab shaped to be lowered into a pipe in a well containing a liquidand comprising a tubular mandrel, a semi-cylindrical anchor fitted toand removable from the mandrel, upper and lower sealing member sectionsfastened to the anchor, a semi-cylindrical carrier mounted on themandrel opposite the anchor, sleeves on the upper and lower ends of thecarrier fitted around and slidable along the mandrel and spaced adistance apart greater than the length of the anchor, upper and lowersealing member sections fastened to the carrier, said sealing membersections on the carrier being movable, by the liquid as the swab islowered therethrough into upper position in staggered relation with thesealing member sections on the anchor to provide a passageway for theliquid between the sections, said sections on the anchor being movableinto confronting relationship with the correspondiig sections on thecarrier as the swab is moved upwardly through the liquid to thus formcomplete upper and lower sealing means between the mandrel and the wallsof the well, said anchor being of such length as to allow said sealingmember sections to move into said two nositions only.

AUGUSTINE PARMESON.

